The rules do not say 1 class
Not addressed in this class document.
- Runabout Rec Lites · RRL
IJSBA · Engine
Aftermarket valve springs and retainers
Often the only cylinder-head part legal in a stock class.
Where it stands, class by class
14 classes, grouped by the answer rather than listed one by one, because an answer that holds for a class usually holds for every class that borrows its rules.
Legal, within limits 1 class
IJSBA-approved valves, valve springs and retainers. Conflicts with the OEM weight/dimension rule elsewhere - verify.
- Four Stroke Ski Lites · FSKL
Legal, within limits 1 class
Listed as allowed in one place and as requiring IJSBA approval per RNA.3.9 in another. Verify.
Legal, within limits 1 class
Aftermarket springs and retainers in the 0-1100cc category ONLY. In 1101-1500cc, springs and retainers must be OEM. · SKM.4.5
Legal, within limits 1 class
Aftermarket retainers with OEM springs; valves, seats, springs and pushrods may be modified or aftermarket. Titanium prohibited unless originally equipped.
- Runabout Limited · RAL
Legal, within limits 1 class
Titanium valves, pushrods and seats prohibited unless originally equipped. · RSS.3.10, RSS.3.12
Legal 6 classes
Explicitly permitted by this class document.
- Fixed Steering Ski Stock · FSSK
- Ski Superstock · SKSS
- Freestyle · FREST
- Ski Grand Prix · SKGP
- Sport GP · SPGP
- Runabout Open / GP · ROP
Legal 1 class
Valve springs and valve spring retainers allowed; replacement valves and seats at OEM weights and dimensions.
- Ski Stock · SSK
Legal 1 class
RAS.3.5
- Runabout Stock · RAS
Aftermarket valve springs and retainers: if the rule your class applies reads differently to you, or the rulebook has changed since this was read, ask. We answer with the section we read it from, or that we have not read it. Ask a rules question.
Every IJSBA class · where the rulebooks differ · signed checks on parts the shop sells.
Engine · four stroke · legal outright in 13 of 14